The present invention disclosed herein relates to an air charging apparatus driven by a rotating magnetic field, which increases the volumetric efficiency of an internal combustion engine and compressing and pressurizing air in order to supply compressed or pressurized air to a fuel cell vehicle.
Various driving types of air supply devices are being used to increase the volumetric efficiency of an internal combustion engine and thus improve the output of the internal combustion engine and the acceleration performance of a vehicle.
Compared to a supercharging vehicle including a supercharging device which compresses and transfers intake air using power of the internal combustion engine, a motor cycle and a natural aspirated vehicle mounted with an natural aspiration internal combustion engine which inhales air using an intake negative pressure and a pressure difference of the atmospheric pressure are low in load failure rate of the internal combustion engine, emit steady output even at high RPM, and are good in instant reaction. However, since air volume flow inhaled into a combustion chamber in intake stroke is not sufficient due to air intake resistance compared to actual displacement volume, there is a limitation in increasing the output. In order to overcome this limitation, a natural aspirated vehicle and a motor cycle to which an inertia pressurization supercharging air supply type of a ram charging system using vehicle speed is applied is being used. However, even in this case, the air density of head wind increases only at high-speed driving and thus the volumetric efficiency increases.
Also, as representative supercharging devices applied to the supercharging vehicles, there are a turbocharger using exhaust gas energy of the internal combustion engine and a supercharger using a crankshaft torque of the internal combustion engine.
The turbocharger is mounted onto the outlet side of an exhaust manifold of the internal combustion engine to use exhaust gas energy increasing in accordance with the load of the internal combustion engine and thus drive a turbine wheel, and a compressor wheel directly connected to the turbine wheel compresses intake air to increase the air density and supply air to an inlet pipe of the internal combustion engine. Thus, the volumetric efficiency increases, and the output of the internal combustion engine is improved. On the other hand, the supercharger operates the compressor using a torque of the crankshaft, and the compressor compresses intake air to increase the air density and supply air into the inlet pipe of the internal combustion engine. Thus, the volumetric efficiency increases, and the output of the internal combustion engine is improved.
However, the supercharging vehicle equipped with the turbocharger acquires sufficient super pressure in a high-speed driving region, but cannot obtain desired boost due to efficiency reduction caused by low exhaust gas energy in a low-speed driving region. Accordingly, a response time delay of a vehicle occurs upon load variation in the low-speed driving region and transient section. Also, since the supercharging vehicle equipped with the supercharger operates the compressor in proportion to RPM of the crankshaft, the response characteristics of a vehicle is good upon load variation of the internal combustion engine, but the driving loss of the internal combustion engine increases in accordance with an increase of RPM of the crankshaft.
As described above, the supercharging vehicles equipped with the turbocharger and the supercharger have opposite advantages and disadvantages to each other in the low-speed and high-speed driving regions. In order to overcome these limitations, a variable turbocharger, a two-stage turbocharger system, a twincharger, an integral electric assisting turbocharger system, and a complex sequential supercharging system are being variously applied to obtain necessary super pressure in the whole driving region of a vehicle and thus increase the volumetric efficiency. In the variable turbocharger, a vane nozzle is installed at the side of turbine. The vane angle of the nozzle is reduced to increase the flow velocity in a low-speed driving region in which the exhaust gas flow rate is deficient, and the vane angle is opened to increase the flow rate of the exhaust gas in a high-speed driving region. In the two-stage turbocharger system, large-capacity and small-capacity turbocharger are connected in series to optimize the performance in accordance with the operation of the internal combustion engine. In the twincharger, the turbocharger and the supercharger operate at the same time in a low-speed driving region, and only the turbocharger operates in a high-speed driving region. In the integral electric assisting turbocharger system, a motor is installed in a central housing part of an existing turbocharger. Also, in the complex sequential supercharging system, a motor compressor and a large-capacity turbocharger are combined. However, in these complex supercharging devices, the increase of the number of parts, the complication of the structure, the addition of a control system cause the increase of cost.
Also, in case of an internal combustion engine ignited at an air-fuel ratio like gasoline fuel, when a supercharging device is applied, due to supercharged air increase in temperature, knocking easily occurs from the compression ratio of the internal combustion engine. Accordingly, the super pressure is difficult to increase to a certain level. On the other hand, when the super pressure is supplied at a low level, it is difficult to expect the increase of the output, and when the compression ratio of the internal combustion engine is lowered and the super pressure is increased, a high output can be obtained in the whole load, but the fuel efficiency is reduced in a partial load. Accordingly, great care is needed for application according to the purpose of the supercharger. The gasoline internal combustion engine equipped with the supercharger includes a knocking sensor, a knocking protecting device such as a device for injecting water mixed with ethanol, and a large-capacity intercooler to lower the supercharging temperature and thus deal with knocking.
Also, in the supercharging internal combustion engine equipped with the turbocharger and the supercharger, fuel is additionally consumed to drive the supercharger and generate compressed air in addition to fuel consumption necessary for improvement of volumetric efficiency.
Also, since the turbocharger is mounted on the side of the outlet of the exhaust manifold and the supercharger needs to be aligned with a belt connected to the crankshaft supplying the power, the location and the direction of the mounting space are restricted, complicating the arrangement of parts of the internal combustion engine.
The turbocharger is equipped with an oil supply device for protecting bearing supporting the turbine wheel rotating at a high speed from exhaust heat, and a driving power of an oil pump is additionally needed to increase the oil pressure of the internal combustion engine.
Also, a vehicle driven by the power of the internal combustion engine needs to satisfy the CO2 emission according to the emission regulation for the global warming. As the downsizing of the internal combustion engine and the increase of the specific power are needed in accordance with the high oil price, the supercharger needs to produce and supply supercharged air having high super pressure. Thus, durability and cooling performance corresponding to the increasing supercharging temperature need to be complemented, while the temperature of the supercharged air needs to be lowered.
In the supercharging vehicle, the superchargers are developed into high supercharging types that generate high super pressure using power of the internal combustion engine while having advantages and disadvantages. The internal combustion engines of the supercharging vehicles have a structure absorbing a supercharger driving load and a cooling device. Since the superchargers receive power of the internal combustion engine to perform necessary operations by controllers of components, air volume flow could not be controlled and supplied corresponding to the characteristics of the internal combustion engine and the vehicle.
Accordingly, air volume flow corresponding to the characteristics of the internal combustion engine and the vehicle having durability to supercharging needs to be supplied to increase the volumetric efficiency. In a low-speed driving region and transient section, the torque needs to be increased to shorten the spool-up time and thus improve the response characteristic of a vehicle. In order to increase a deficient super pressure supplied by an existing supercharger in a low-speed region, the fuel consumption needs to be reduced. Also, the load of the internal combustion engine operated in order to maintain the super pressure in a high-speed driving region needs to be reduced. Thus, an air supply device corresponding to the internal combustion engine having high specific power according to the carbon emission regulation and the downsizing trend of a vehicle is needed. Without giving a load to a vehicle and an internal combustion engine, the temperature of supplied air is low and the air density is relatively high compared to an existing supercharger. In such air supply device, the driving loss and driving noise are lower, and the durability is better. Also, the air supply device uses low power or does not need the driving cost, and can be easily installed without limitations of a specific location and a mounting direction.
Also, in the natural aspirated vehicle and motor cycle, since air is not charged corresponding to actual displacement volume due to the air intake resistance, there is a limitation in increasing the output. Accordingly, in order to increase the volumetric efficiency, an inertial pressurization supercharging air supply type of ram charging system using the vehicle speed may be applied.
However, the inertia pressurization supercharging air supply type can achieve an effect of increasing the volumetric efficiency because the air density of head wind increases only at high-speed driving.
Accordingly, there is a need for an air supply device which supplies air volume flow corresponding to the characteristics of the natural aspiration internal combustion engine, the natural aspirated vehicle, and the motor cycle within an error correction range of the driving system and the control system while maintaining the advantages of the natural aspirated vehicle and the motor cycle, increases the volumetric efficiency, deals with the carbon emission regulation by reducing the fuel consumption of the internal combustion engine, and improves the acceleration force in the transient section. Thus, without giving a load to the vehicle and the internal combustion engine, the driving loss and driving noise are lower, and the durability is better. Also, the air supply device uses low power or does not need the driving cost, and can be easily installed without limitations of a specific location and a mounting direction.
Also, in a fuel cell vehicle, an air supply system of a fuel cell driving device is using an air blower or an electric air compressor for supplying air that is an oxidant to a fuel cell.
However, since the electric air compressor uses power produced in the fuel cell or battery charged power, the capacity and the volume of the fuel cell and the battery become larger, inevitably affecting the travelling distance of a vehicle.
Accordingly, in order to overcome the above limitation, an air supply device that supplies air volume flow corresponding to the characteristics of the fuel cell to the fuel cell driving device of the fuel cell vehicle is needed. Thus, without giving a load to the vehicle, the driving loss and the driving noise become lower, and the durability becomes better. Also, the air supply device is operated by lower power than the electric air compressor.